CN101916993A - Arc extinction system for power grid - Google Patents
Arc extinction system for power grid Download PDFInfo
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- CN101916993A CN101916993A CN 201010259062 CN201010259062A CN101916993A CN 101916993 A CN101916993 A CN 101916993A CN 201010259062 CN201010259062 CN 201010259062 CN 201010259062 A CN201010259062 A CN 201010259062A CN 101916993 A CN101916993 A CN 101916993A
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Abstract
The invention relates to an arc extinction system for a power grid. The bus of the power grid comprises a main loop and a plurality of subloops, wherein the main loop and each subloop are respectively provided with an arc extinction cabinet; the arc extinction cabinet comprises an overvoltage protector, a detection unit, a microcomputer integrated controller and an arc extinction unit; the main loop and each subloop are respectively provided with a zero sequence mutual inductor; the arc extinction cabinet also comprises a low current route selection device; the detection unit is used for detecting whether an arc fault exists in the loop where the detection unit is positioned and sending an arc extinction instruction to the arc extinction unit if the arc fault exists; the zero sequence mutual inductor is used for detecting whether induction current is generated in the loop where the arc fault exists and transmitting the induction current to the low current route selection device if the induction current is generated; the low current route selection device is used for generating an enabled instruction according to the transmitted induction current and transmitting the enabled instruction to the arc extinction unit; and the arc extinction unit is used for performing arc extinction after receiving the arc extinction instruction and the enabled instruction. The invention also provides the arc extinction cabinet. The arc extinction system can be applied to the arc extinction of the multistage power grid and improve the stability of the power grid.
Description
Technical field
The present invention relates to the electrical network change and send electrical domain, particularly a kind of arc extinction system for power grid.
Background technology
The electrical network of China 3～66KV adopts the operational mode of isolated neutral mostly, when the direct ground connection of Single Phase Metal is taken place, the voltage to earth of non-fault phase will be elevated to line voltage, the three-phase line voltage value is constant, and still have the phase difference of 120 degree, the work of three-phase power consumption equipment is not affected, thereby does not influence the normal transmission of electric energy, so this class electrical network of national Specification allows the short time to operate with failure after single phase ground fault takes place, so that the sustainable power supply of such electrical network.
Existing operating standard regulation, during system with non effectively earth ed neutral generation single phase ground fault, allow operation two hours, if single phase ground fault is a metallic earthing, then the voltage of fault phase reduces to zero, all the other two perfect phase-to-ground voltage and are increased to line voltage, and the electric equipment of this class electrical network under normal circumstances all should be able to bear this overvoltage and not damage.But, if single phase ground fault is intermittent arc grounding (hereinafter to be referred as the arcing ground fault), then can in system, produce the overvoltage that reaches 3.5 times of phase voltage peak values, if high like this overvoltage a few hours act on electrical network, certainly will cause the accumulation damage of insulation in the electric equipment, cause insulation to puncture over the ground in the insulation weak link that perfects phase, and then develop into the phase fault accident.In intermittent arcing ground transient process, real system can form the multifrequency oscillation circuit, not only can produce the overvoltage relatively of high amplitude, but also the alternate overvoltage of high amplitude may occur, makes phase insulation weakness flashover, develops into the phase fault accident
Be to introduce arc extinction cabinet to one of extinguishing arc solution of arcing ground fault at present, referring to Fig. 1, arc extinction cabinet comprises overvoltage protection device 11, detecting unit 12, microcomputer general controller 13 and arc extinction unit 14.When the overvoltage of high amplitude appearred in system, combination overvoltage protector 11 was at first devoted oneself to work, with system's overvoltage Limiting in the safe range that insulation of electrical installation allows; When ground connection or resonance fault take place in protected system; voltage transformer TV in the detecting unit 12 provides the instantaneous value delta data of three-phase voltage U a, Ub, Uc and open delta voltage U0; microcomputer general controller 13 is judged the character of fault according to the instantaneous value delta data; send corresponding instruction control arc extinction unit 14 and carry out corresponding action, carry out extinguishing arc.The extinguishing arc mode mainly contains following several:
1. if the fault of Fa Shenging is a unstable arc ground connection, microcomputer general controller 13 is sent instruction after judging ground connection separate, make the high-pressure vacuum contactor (KA or KB or KC) of fault phase in the arc extinction unit 14 closed at short notice; Extinguishing arc voltage limiter XYQ in the arc extinction unit 14 is inserted the ground connection phase, and the recovery voltage of fault restriction phase absorbs the electromagnetic energy that ground connection causes, the relieving system vibration makes recovery voltage breakdown fault point and blow-out once more; When the detection system three-phase voltage is normal value, after the second of delaying time again, make high-pressure vacuum contactor disconnect, system restoration normally moves;
2. if the fault of Fa Shenging is a stable arc ground connection, microcomputer general controller 13 is after judging ground connection separate, make the high-pressure vacuum contactor KD of the corresponding vacuum contactor of fault (KA or KB or KC) and ground connection in the arc extinction unit 14 closed simultaneously, make system be quickly converted to the direct ground connection of stable metallicity by the arc grounding of stability, the fault phase voltage reduces to zero, and electric arc disappears; After several seconds, the high-pressure vacuum contactor KD of Schilling ground connection disconnects, at this moment insert extinguishing arc voltage limiter XYQ in the arc extinction unit 14 mutually in fault, the resume speed of fault restriction phase voltage and amplitude, the relieving system vibration, disconnect the second of delaying time, if fault disappears, illustrate that this arcing ground fault is to impact the instantaneity earth fault that causes because of overvoltage, system restoration normally moves; After if contactor KD disconnects, system stable arc ground connection occurs mutually in former fault once more, device assert that this fault is nonvolatil arcing ground fault, so the high-pressure vacuum contactor KD of closed once more fault phase and ground connection waits for operator on duty or microcomputer route selection processing;
Putting it briefly, is exactly the data that microcomputer general controller 13 provides according to detecting unit 141, judges the character of fault, sends corresponding instruction control arc extinction unit 14 and carries out corresponding action, and electric arc is eliminated.After electric arc was eliminated, electrical network may return to normal condition, also may remain on the malfunction of Single Phase Metal ground connection, existing operating standard regulation, and electrical network also allows operation two hours under this state.
In the above-mentioned existing arc extinguishing method, arc extinction cabinet is come the character of failure judgement according to the variation of line voltage instantaneous value, sends corresponding instruction, carries out extinguishing arc.And the variation of line voltage is can be simultaneous on same bus section, busbar section, if only be that it is no problem introducing arc extinction cabinet under the situation of electric substation's service at one section bus; If one section bus of higher level electric substation is the power supply of a plurality of level of factory electric substation, and when being provided with arc extinction cabinet on the bus of each electric substation, arc fault occurs, the arc extinction cabinet of each electric substation all can be moved, and can influence just row operation of electrical network but each arc extinction cabinet extinguishing arc action is inconsistent.
Consult Fig. 2, A0-An represents to be installed in the arc extinction cabinet of different location among Fig. 2, the higher level power transformation example of doing, if arc fault over the ground relatively takes place in the A in higher level electric substation loop 1, then the instantaneous value of the 10KV bus A phase voltage of higher level electric substation will change, the detecting unit of arc extinction cabinet A0 will detect associated change, makes arc extinction unit carry out relevant action.Can both be detected but the variation of A phase voltage instantaneous value is all electric substations, arc extinction cabinet A1-An also can carry out relevant action.The priority of variant in this case arc extinction cabinet action depends on the different differences of each arc extinction cabinet, might cause the arc extinction cabinet at short dot place also not have action, and the situation that other arc extinction cabinet is moved earlier, perhaps many situations that arc extinction cabinet is moved simultaneously in the electrical network.Like this, each arc extinction cabinet according to each self-monitoring situation input protection, withdraws from protection again; each arc extinction cabinet or through extinguishing arc voltage limiter ground connection, or the direct ground connection of metallicity, or withdraw from ground connection; will cause electrical network to produce unusual complicated ground connection situation, influence malfunction elimination and electrical network normally moves.
Therefore, existing arc extinction cabinet only is applicable to the situation of the single electric substation of electrical network band, and does not fit into the situation of a plurality of different electric substations of electrical network band.
Summary of the invention
Purpose of the present invention provides a kind of arc extinction system for power grid, the applicable multistage electric wire netting arc extinguishing of this arc-extinguishing system, and the stability of raising electrical network.
A kind of arc extinction system for power grid of the present invention; the electrical network bus comprises major loop and a plurality of sub-loop; described major loop and each sub-loop are equipped with arc extinction cabinet; described arc extinction cabinet comprises overvoltage protection device, detecting unit, microcomputer general controller and arc extinction unit; zero-sequence transformer is installed in described major loop and each sub-loop respectively, and described arc extinction cabinet also comprises little electric current line selection apparatus:
Described detecting unit is used to detect the loop, place whether arc fault takes place, and as arc fault takes place, sends extinguishing arc and instructs arc extinction unit;
Described zero-sequence transformer is used for whether having induced current to generate in the loop of detecting the generation arc fault, if any, transmit induced current to described little electric current line selection apparatus;
Described little electric current line selection apparatus is used for sending arc extinction unit according to sending induced current production enabled instruction;
Described arc extinction unit is used for carrying out the extinguishing arc action after receiving extinguishing arc instruction and enabled instruction.
Preferably, arc extinction unit comprises judgment sub-unit, time-delay subelement and extinguishing arc subelement;
Described judgment sub-unit is used for judging the arc extinction cabinet position after receiving extinguishing arc instruction and enabled instruction, when being arranged on major loop as arc extinction cabinet, starts described time-delay subelement; When being arranged on sub-loop, start described extinguishing arc subelement as arc extinction cabinet;
Described time-delay subelement behind the Preset Time that is used to delay time, starts the extinguishing arc subelement;
The described orphan unit that disappears is used to carry out the extinguishing arc action.
The present invention also provides a kind of electric wire netting arc extinguishing cabinet, the applicable multistage electric wire netting arc extinguishing of this arc extinction cabinet, and the stability of raising electrical network.
A kind of arc extinction cabinet of the present invention comprises overvoltage protection device, detecting unit, microcomputer general controller and arc extinction unit, and zero-sequence transformer is installed in described major loop and each sub-loop respectively, and described arc extinction cabinet also comprises little electric current line selection apparatus:
Described detecting unit is used to detect the loop, place whether arc fault takes place, and as arc fault takes place, sends extinguishing arc and instructs arc extinction unit;
Described zero-sequence transformer is used for whether having induced current to generate in the loop of detecting the generation arc fault, if any, transmit induced current to described little electric current line selection apparatus;
Described little electric current line selection apparatus is used for sending arc extinction unit according to sending induced current production enabled instruction;
Described arc extinction unit is used for carrying out the extinguishing arc action after receiving extinguishing arc instruction and enabled instruction.
Preferably, arc extinction unit comprises judgment sub-unit, time-delay subelement and extinguishing arc subelement;
Described judgment sub-unit is used for judging the arc extinction cabinet position after receiving extinguishing arc instruction and enabled instruction, when being arranged on major loop as arc extinction cabinet, starts described time-delay subelement; When being arranged on sub-loop, start the described orphan unit that disappears as arc extinction cabinet;
Described time-delay subelement behind the Preset Time that is used to delay time, starts the extinguishing arc subelement;
Described extinguishing arc subelement is used to carry out the extinguishing arc action.
Compared with prior art, the present invention has the following advantages:
The present invention detects the space vector state of three-phase current in major loop and each sub-loop by zero-sequence transformer, judge the concrete loop that sends arc fault, arc extinction cabinet on this loop of instruction is carried out extinguishing arc, avoid a plurality of arc extinction cabinet to move simultaneously and make electrical network ground state complexity, the applicable multistage electric wire netting arc extinguishing of this arc-extinguishing system, and the stability of raising electrical network.
Description of drawings
Fig. 1 is existing arc extinction cabinet schematic diagram;
Fig. 2 is existing arc-extinguishing system schematic diagram;
Fig. 3 detects schematic diagram for loop of the present invention induced current;
Fig. 4 is an arc extinction system for power grid schematic diagram of the present invention;
Fig. 5 is the single loop of an arc extinction system for power grid of the present invention schematic diagram;
Fig. 6 is an arc extinction unit structural representation of the present invention.
Embodiment
For above-mentioned purpose of the present invention, feature and advantage can be become apparent more, the present invention is further detailed explanation below in conjunction with the drawings and specific embodiments.
Referring to Fig. 3, loop of the present invention induced current is shown detects schematic diagram, each loop outlet is equipped with zero-sequence transformer 15, and the outlet cable passes zero-sequence transformer 15, and zero-sequence transformer 15 secondary sides insert little electric current line selection apparatus 16.Under the normal condition, the space vector of the three-phase current of outlet cable and be zero, zero-sequence transformer 15 secondary sides do not have induced current; If arc fault takes place in certain loop, for example arc fault takes place in the A in loop 2 mutually, has earth current to take place mutually and between the ground at A, the space vector of the three-phase current of the outlet cable in loop 2 and non-vanishing, and zero-sequence transformer 15 secondary sides generate induced current.This induced current is sent to little electric current line selection apparatus 16, and electric current line selection apparatus 16 just can be judged arc fault and occur in which loop.Electric current line selection apparatus 16 can be used as the part of arc extinction cabinet.
Referring to Fig. 4 and Fig. 5, arc extinction system for power grid schematic diagram of the present invention is shown, major loop is higher level's substation busbars, and each sub-loop is joined chamber (electric substation of subordinate) bus for each height, and major loop and each sub-loop are equipped with zero-sequence transformer 15 and arc extinction cabinet.Be provided with overvoltage protection device 11, detecting unit 12, microcomputer general controller 13 and arc extinction unit 14 and little electric current line selection apparatus 16 in the arc extinction cabinet, little electric current line selection apparatus 16 is connected with zero-sequence transformer 15 on the same loop.
Detecting unit 12 detects the loops, place whether arc fault takes place, and as arc fault takes place, send extinguishing arc and instruct arc extinction unit 14, but arc extinction unit 14 is failure to actuate; Whether the zero-sequence transformer 15 on the loop of generation arc fault detects these loops has induced current to generate, if any, transmit induced current to little electric current line selection apparatus 16; Little electric current line selection apparatus 16 sends arc extinction unit 14 according to sending induced current production enabled instruction, and arc extinction unit is carried out the extinguishing arc action.
Illustrate, if No. 1 arc fault takes place in the high loop, chamber 11 of joining, little electric current line selection apparatus 16 in the arc extinction cabinet A1 can send enabled instruction and give arc extinction unit 14, arc extinction unit 14 in the arc extinction cabinet A1 is carried out the extinguishing arc action, though and No. 2 adjacent high arc extinction cabinet A2 that join on the loop, chamber have also detected the line voltage unusual fluctuations, but because of the little electric current line selection apparatus 16 in the arc extinction cabinet A2 is not produced induced current, the arc extinction unit 14 in the arc extinction cabinet A2 can not moved.
The present invention detects the space vector state of three-phase current in major loop and each sub-loop by zero-sequence transformer, judge the concrete loop that sends arc fault, arc extinction cabinet on this loop of instruction is carried out extinguishing arc, avoid a plurality of arc extinction cabinet to move simultaneously and make electrical network ground state complexity, the applicable multistage electric wire netting arc extinguishing of this arc-extinguishing system, and the stability of raising electrical network.
Solve the problem that arc extinction cabinet is used like this in multistage electrical network, improved the stability of electrical network.
But under the above-mentioned situation, the zero-sequence transformer 15 that is provided with on higher level's electrical network loop of No. 1 high chamber of joining power supply but can be examined the generation induced current, causes the arc extinction unit 14 in the arc extinction cabinet A0 to carry out the extinguishing arc action.For avoiding this situation to take place, the present invention is provided with the time-delay subelement in arc extinction unit 14, by deferred action, avoid the arc extinction unit 14 of two arc extinction cabinet to move simultaneously, produces conflict.
Referring to Fig. 6, arc extinction unit 14 comprises judgment sub-unit 141, time-delay subelement 142 and extinguishing arc subelement 143.
Judgment sub-unit 141 when being arranged on major loop as arc extinction cabinet, starts time-delay subelement 142 after the enabled instruction of extinguishing arc instruction that receives detecting unit 12 and little electric current line selection apparatus 16; When arc extinction cabinet is arranged on sub-loop, directly start described extinguishing arc subelement 143.Behind the time-delay subelement 142 time-delay Preset Times, restart extinguishing arc subelement 143; Extinguishing arc subelement 143 carries out the extinguishing arc action.
Like this, detecting unit 12 in the arc extinction cabinet A0 sends extinguishing arcs and instructs arc extinction unit 14, little electric current line selection apparatus 16 in the arc cabinet A0 sends enabled instruction to arc extinction unit 14 simultaneously, because of arc extinction cabinet A0 is arranged on the major loop, time-delay subelement 142 starts, behind the time-delay Preset Time, arc extinction unit 14 is moved again.Be engraved in after the arc extinction cabinet A1 when making the action of arc extinction cabinet A0.After the arc extinction cabinet A1 action, arc fault has been converted into the direct ground connection of metallicity like this, and arc extinction cabinet A0 does not just need to have moved again.
The invention solves the problem that arc extinction cabinet is used in multistage electrical network, improved the stability of electrical network, for fault analysis and handling provides information more accurately.
The present invention also provides a kind of arc extinction cabinet, and the 26S Proteasome Structure and Function of this arc extinction cabinet is identical with above-mentioned arc extinction cabinet, repeats no more.
The above only is a preferred implementation of the present invention, does not constitute the qualification to protection range of the present invention.Any any modification of being done within the spirit and principles in the present invention, be equal to and replace and improvement etc., all should be included within the claim protection range of the present invention.
Claims (4)
1. arc extinction system for power grid; the electrical network bus comprises major loop and a plurality of sub-loop; described major loop and each sub-loop are equipped with arc extinction cabinet; described arc extinction cabinet comprises overvoltage protection device, detecting unit, microcomputer general controller and arc extinction unit; it is characterized in that; zero-sequence transformer is installed in described major loop and each sub-loop respectively, and described arc extinction cabinet also comprises little electric current line selection apparatus:
Described detecting unit is used to detect the loop, place whether arc fault takes place, and as arc fault takes place, sends extinguishing arc and instructs arc extinction unit;
Described zero-sequence transformer is used for whether having induced current to generate in the loop of detecting the generation arc fault, if any, transmit induced current to described little electric current line selection apparatus;
Described little electric current line selection apparatus is used for sending arc extinction unit according to sending induced current production enabled instruction;
Described arc extinction unit is used for carrying out the extinguishing arc action after receiving extinguishing arc instruction and enabled instruction.
2. the system as claimed in claim 1 is characterized in that, arc extinction unit comprises judgment sub-unit, time-delay subelement and extinguishing arc subelement;
Described judgment sub-unit is used for judging the arc extinction cabinet position after receiving extinguishing arc instruction and enabled instruction, when being arranged on major loop as arc extinction cabinet, starts described time-delay subelement; When being arranged on sub-loop, start described extinguishing arc subelement as arc extinction cabinet;
Described time-delay subelement behind the Preset Time that is used to delay time, starts the extinguishing arc subelement;
Described extinguishing arc subelement is used to carry out the extinguishing arc action.
3. an arc extinction cabinet comprises overvoltage protection device, detecting unit, microcomputer general controller and arc extinction unit, it is characterized in that, zero-sequence transformer is installed in described major loop and each sub-loop respectively, and described arc extinction cabinet also comprises little electric current line selection apparatus:
Described detecting unit is used to detect the loop, place whether arc fault takes place, and as arc fault takes place, sends extinguishing arc and instructs arc extinction unit;
Described zero-sequence transformer is used for whether having induced current to generate in the loop of detecting the generation arc fault, if any, transmit induced current to described little electric current line selection apparatus;
Described little electric current line selection apparatus is used for sending arc extinction unit according to sending induced current production enabled instruction;
Described arc extinction unit is used for carrying out the extinguishing arc action after receiving extinguishing arc instruction and enabled instruction.
4. arc extinction cabinet as claimed in claim 3 is characterized in that arc extinction unit comprises judgment sub-unit, time-delay subelement and extinguishing arc subelement;
Described judgment sub-unit is used for judging the arc extinction cabinet position after receiving extinguishing arc instruction and enabled instruction, when being arranged on major loop as arc extinction cabinet, starts described time-delay subelement; When being arranged on sub-loop, start described extinguishing arc subelement as arc extinction cabinet;
Described time-delay subelement behind the Preset Time that is used to delay time, starts the extinguishing arc subelement;
Described extinguishing arc subelement is used to carry out the extinguishing arc action.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN2010102590626A CN101916993B (en) | 2010-08-18 | 2010-08-18 | Arc extinction system for power grid |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN2010102590626A CN101916993B (en) | 2010-08-18 | 2010-08-18 | Arc extinction system for power grid |
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| Publication Number | Publication Date |
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| CN101916993A true CN101916993A (en) | 2010-12-15 |
| CN101916993B CN101916993B (en) | 2012-11-21 |
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| Application Number | Title | Priority Date | Filing Date |
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| CN2010102590626A Active CN101916993B (en) | 2010-08-18 | 2010-08-18 | Arc extinction system for power grid |
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Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN104502796A (en) * | 2014-12-10 | 2015-04-08 | 安徽国科电力设备有限公司 | Low-current line selection device for wireless networking |
Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH11122915A (en) * | 1997-10-17 | 1999-04-30 | Canon Inc | Power unit |
| CN2485855Y (en) * | 2001-02-12 | 2002-04-10 | 合肥南南电力保护设备有限公司 | Arc eliminator for ground system with neutral point grounded indirectly |
| CN101707369A (en) * | 2009-03-17 | 2010-05-12 | 郭道胜 | Arc and resonance elimination comprehensive device for power grid |
-
2010
- 2010-08-18 CN CN2010102590626A patent/CN101916993B/en active Active
Patent Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH11122915A (en) * | 1997-10-17 | 1999-04-30 | Canon Inc | Power unit |
| CN2485855Y (en) * | 2001-02-12 | 2002-04-10 | 合肥南南电力保护设备有限公司 | Arc eliminator for ground system with neutral point grounded indirectly |
| CN101707369A (en) * | 2009-03-17 | 2010-05-12 | 郭道胜 | Arc and resonance elimination comprehensive device for power grid |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN104502796A (en) * | 2014-12-10 | 2015-04-08 | 安徽国科电力设备有限公司 | Low-current line selection device for wireless networking |
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| CN101916993B (en) | 2012-11-21 |
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